Horton was born in Chesterton, Staffordshire, England, UK, on 4 February 1879. In 1901, she attended Queen Victoria’s funeral. In 1905, she married Henry Enoch Horton in London. In 1910, the couple moved to Canada, settling in Nelson, British Columbia. Her husband was a Methodist minister who served seven churches in Vancouver over the period of 40 years, before retiring at the age of 70. The couple had four children: Rev. E.W. Horton, Ruby Berridge, Nora Davis and Mary Lockwood.
Her husband passed away in 1968, at the age of 85. At the age of 107, she lived with her daughter Ruby Berridge in the neighbourhood of West End.
Horton passed away in Vancouver, British Columbia, Canada, on 26 February 1989, at the age of 110 years, 22 days. She was survived by her four children, 5 grandchildren, and eight great-grandchildren.
At the time of death, the was the fourth-oldest living person in Canada, behind Nellie Thompson (born 21 Oct 1878), Alice Sjoquist (born 25 Oct 1878) and Alina Morton (born 10 Nov 1878). Furthermore, she was the second-oldest living person in the Province of British Columbia, behind Sjoquist.
Her age was validated by the ESO on 28 July 2023, and later recognized by LongeviQuest.
* “Friday was a big day for the ladies” – The Vancouver Sun, 5 February 1983
* “Premier Bennett’s speech? Mary’s heard it all before” – The Vancouver Sun, 8 February 1986
* “A birthday orchid is admired by 109-year-old Mary Horton” – The Vancouver Sun, 5 February 1988
* “HORTON Mary Janettie” – The Vancouver Sun, 2 March 1989